Proceeding at a Grinding Machine and a Device for the Same

ABSTRACT

The invention concerns proceeding and device for facilitating the handling of a manually drivable and mechanically operable grinding machine ( 1 ) for floors ( 3 ) and other similar surfaces and which grinding machine ( 1 ) comprises a rotatable grinding disc ( 2 ), which is driven by a motor ( 5 ) and carried by an articulated motor housing ( 9 ) supporting the grinding disc on the chassis ( 10 ) of the machine. According to the invention, the motor housing ( 9 ) in question is counterbalanced so that the same becomes balanced in relation to the chassis ( 10 ) of the machine.

The present invention concerns a proceeding for facilitating the handling of a manually drivable and mechanically operable grinding machine for floors and other similar surfaces and which grinding machine comprises a rotatable grinding disc, which is driven by a motor and carried by an articulated motor housing supporting the grinding disc on the chassis of the machine.

In operation using such grinding machines, intended to be used on floors and which normally have supporting wheels at the rear part thereof and a grinding wheel under the machine at the front part thereof and which the machine operator follows and holds in a handle having controls for the machine, there are problems especially in case of machines having a greater grinding disc in that the machine easily pulls in a direction and this then clearly means a considerably more uncomfortable operation position with risk of wearing injuries to the operator as a consequence. The now existing floor grinding machines, which are provided with motors of miscellaneous types, such as internal combustion engine driven, electric and gas driven, are not so ergometrically correctly designed and constructed. Therefore, it is desired to bring about that the operator by as little force as possible should be able to use the machine and in such a way be able to work a whole day without becoming tired due to the machine pulling in a direction.

Therefore, the main object of the present invention is primarily to efficiently, ergometrically correctly as well as in a cost-saving way solve said problems.

Said object is achieved by means of a proceeding according to the present invention, which essentially is characterized in that, in order to allow counterbalancing the motor housing in question, so that the same becomes balanced in relation to the chassis of the machine, at least one spring is utilized as balancing aid so that the same counteract(s) weight/torque from the motor carried by the motor housing.

The invention also concerns a device for the realisation of a proceeding as mentioned above.

Also in such a known device, there are the problems indicated above. Therefore, a further object of the present invention is also to solve said problems.

Said further object is solved by means of a device according to the present invention, which essentially is characterized in that means for counterbalancing the motor housing in relation to the chassis of the machine is arranged to extend between the same so that said means compensates possible imbalance between the motor housing and said chassis of the machine, said means being comprised of at least one spring, which is arranged between the motor housing and the chassis of the machine so that said spring is connected to counterbalance the parts of the motor and possible other biased parts thereon, that a compression spring and/or a tension spring is arranged for counterbalancing the motor housing and the grinding disc carried thereby, and that said spring is arranged to act between the motor housing and the chassis of the machine on one side of the same interconnected pivot joint, preferably in pairs.

By WO 93/18700, a floor cleaning machine is known, which is provided with a scrubbing or polishing wheel (61) however no grinding machine. There is an essential difference between a stone-dressing machine for concrete floors and other floors intended to be ground down to an even surface and a scrubbing and polishing, or orbital, machine in case of a floor cleaning machine, even if it may seem that the appearance is similar between the two categories of machines.

However, the known floor scrubbing machine has a rotatable scrubbing brush, which is turnably mounted on pivots (7, 8). Springs (17) situated in line with the motor on each side of the centre line of the machine holds a supporting plate (11) in horizontal position in relation to the substratum (22).

According to the present invention, a grinding disc is held in horizontal position in relation to the substratum by being pressed down from the frame of the machine. This has not been shown to be previously known by prior art in the field.

The invention is described below by way of a number of preferred embodiment examples, reference being made to the accompanying drawings, in which

FIG. 1 shows a right side view of a floor grinding machine equipped with shown device according to the invention,

FIG. 2 shows in more detail the invention in close-up,

FIG. 3 shows a side view as seen from the left of a floor grinding machine likewise provided with the invention but which cannot be seen from said side, and

FIG. 4 shows a perspective view of a floor grinding machine obliquely from the front right side.

The invention may, e.g., be applied to a floor grinding machine 1, where a grinding disc 2 shaped as a drum with, e.g., three pads equipped with abrasive segments of desired type rotates in a common direction and the larger disc-shaped drum 2, on which the pads are journally supported, rotates in the opposite direction, wherein the grinding becomes even and that there will be a small pull laterally when one operates and walks with the machine holding a handle 4 on the intended substratum 3, e.g., a concrete floor desired to be evenly ground. Example thereof is shown in FIG. 1 where the handle 4 is held in raised running position I. In FIG. 4, the handle 4 is shown in lowered storage and transport position II. In the example, an electric motor 5 is shown, which is placed mounted relatively central on the machine 1 essentially straight above the balancing point 7 of the motor housing 9. In that connection, there is not such a large risk of imbalance of the machine 1. In machines 1 supporting larger motors 5, e.g., internal combustion engines and gas driven motors and on that occasion often also gearbox therefor since gear reduction of the rotational speeds of the motor is required, heavy weight is put on the rear edge 8 of the machine. This undesired load F₁ at the rear of the machine as well as all other bias acting on the machine 1 and the rotatably driven drum 2 thereof entails that the drum 2 is biased and pressed by different force against the substratum 3. This makes that the machine 1 is actuated to drift in either direction laterally along the substratum 3 and there will be tension load laterally A,B.

In machines provided with heavier motors requiring gear reduction, said problem does not necessarily need to be present solely in case of an internal combustion engine but there is the majority of manufacturers who have solutions to machines where they have loaded gears or other details which make the machine heavy in the rear edge (or front edge) but have not compensated for this. This entails that the machines are pulling laterally. The operator who then has to compensate said lateral pulling by muscular power risks in that connection to be subjected to work-related injuries due to, among other things, inappropriate operating position.

The present invention intends to solve this serious problem by a machine 1 that can be utilized in a proceeding of the above-mentioned type for facilitating the handling of a manually drivable and mechanically operable grinding machine 1 for floors 3 and other similar surfaces and which grinding machine 1 comprises a rotatable grinding disc 2, which is driven by a motor 5 and carried by an articulated motor housing 9 supporting the grinding disc 2 on the chassis 10 of the machine by allowing counterbalancing the motor housing 9 in question so that the same becomes balanced in relation to the chassis 10 of the machine.

This takes place in such a way that at least one spring 11 is utilized as balancing aid arranged so that the same counteract(s) weight/torque from a motor 5 carried by the motor housing 9. Suitably, a tension spring 11 and/or a compression spring are/is utilized, which are/is arranged to counteract the weight/torque from said motor 5 and other weighty parts of the machine.

A device suitable to be applied in the realisation of a proceeding for facilitating the handling of a manually drivable grinding machine 1 for floors 3 and other similar surfaces and which grinding machine 1 comprises rotatable grinding disc 2, which is driven by a motor 5 and carried by an articulated motor housing 9 supporting the grinding disc 2 on the chassis 10 of the machine comprises means for counterbalancing the motor housing 9 in relation to the chassis 10 of the machine and which is arranged to extend between the same so that said means compensates possible imbalance between the motor housing 9 and said chassis 10 of the machine.

Said means is comprised of at least one spring 11, which is arranged between the motor housing 9 and the chassis 10 of the machine so that said spring 11 is connected to counterbalance the parts of the motor 5 and possible other biased parts thereon.

However, suitably two springs 11 are arranged in the indicated way, one spring 11 situated on each side of the motor housing 9, as seen laterally and in the intended direction of travel and longitudinal centre plane 13 of the machine.

A compression spring and/or a tension spring 11 are/is arranged for counterbalancing the motor housing 9 and the grinding disc 2 carried thereby and said spring(s) 11 is/are arranged to act between the motor housing 9 and the chassis 10 of the machine on one side of the same interconnected pivot joint 12, preferably in pairs with a spring 11 arranged on each side A,B of the longitudinal centre plane 13 of the machine as seen in the longitudinal direction 14 of the machine.

For fastening the spring(s) 11 in question, a fixing clamp 30 of the motor housing 9 may perform the function of anchoring the spring(s) 11 with the lower end 15 thereof and that the spring(s) 11 is/are anchored to a suitable portion of the chassis 10 of the machine by the respective upper portion 16 of the spring(s) 11.

Said spring 11 is fixed to the motor housing 9 and the chassis 10 of the machine with the respective ends 15,16 via pivot joints 12, preferably in the form of ball-and-socket joints, and said spring 11 is mounted between the pivot joint 12 for the bearing mounting of the motor housing to the chassis 10 of the machine and a handle 4 intended for the control of the machine 1 and wheels 18 situated at the rear end 19 of the machine just below a cap 20, which conceals parts carried by the chassis 10 for the receipt of grinding dust, etc.

The function and the nature of the invention should clearly have been understood with the aid of the above-mentioned and with reference to the drawings.

The invention is naturally not limited to the embodiments described above and shown in the accompanying drawings. Modifications are feasible, particularly as for the nature of the different parts, or by using an equivalent technique, without departing from the protection area of the invention, such as it is defined in the claims. With grinding machine also other machining machines, which treats essentially horizontal surfaces of stone and the like material, should be comprised. 

1.-9. (canceled)
 10. A method of facilitating handling of a manually drivable and mechanically operable grinding machine for floors and other surfaces, the grinding machine comprising a rotatable grinding disc driven by a motor carried by an articulated motor housing that supports the grinding disc on a chassis of the grinding machine, the method comprising using at least one spring for counterbalancing the motor housing such that the motor housing is balanced in relation to the chassis by counteracting the motor's weight or torque.
 11. The method of claim 10, wherein at least one tension spring is used for counterbalancing the motor housing.
 12. The method of claim 11, wherein at least one compression spring is used for counterbalancing the motor housing.
 13. The method of claim 10, wherein at least one compression spring is used for counterbalancing the motor housing.
 14. An apparatus for realizing the method of claim 10, comprising a mechanism configured for counterbalancing the motor housing in relation to the chassis, wherein the mechanism extends between the motor housing and chassis such that the mechanism compensates imbalance between the motor housing, grinding disc, and chassis; the mechanism includes at least one spring connected between the motor housing and chassis such that the spring counterbalances at least parts of the motor; the at least one spring includes at least one compression spring or tension spring; and the at least one spring is arranged to act between the motor housing and chassis on a respective side of pivot joint that interconnects the motor housing and chassis.
 15. The apparatus of claim 14, wherein respective ends of the at least one spring are attached to the motor housing and to the chassis by respective pivot joints.
 16. The apparatus of claim 15, wherein the pivot joints are ball-and-socket joints.
 17. The apparatus of claim 15, wherein the at least one spring is mounted between a pivot joint and a handle for controlling the grinding machine and wheels situated at a rear end of the grinding machine.
 18. The apparatus of claim 14, wherein the at least one spring includes a spring situated on each side of the motor housing in an intended direction of travel of the grinding machine.
 19. The apparatus of claim 14, wherein the at least one spring is situated behind the motor as seen in a direction of travel forward of the grinding machine and in a longitudinal center plane of the grinding machine.
 20. The apparatus of claim 14, wherein the at least one spring is situated between the pivot joint and rear wheels of the grinding machine. 